Trans fatty acid intake and its association with adenomas and cancers of the colon and rectum

Recently, there has been increasing concern about the health effects of trans fatty acid consumption, however, little is known about its role in digestive tract neoplasia. The goal of this dissertation was to investigate this relationship. The association between trans fatty acid consumption and colorectal adenomas (present throughout the entire colon and rectum) was investigated using the Diet and Health Study IV, a cross-sectional study conducted between 2001 and 2002. The highest quartile of consumption was associated with an increased prevalence of colorectal adenomas, with an adjusted prevalence odds ratio comparing the highest to the lowest quartile of consumption of 1.86 (95%CI 1.04, 3.33). The North Carolina Colon Cancer Study I, a case-control study taking place between 1996 and 2000, was utilized to examine the association for colon cancer (located between the cecum and sigmoid colon). No association was seen between trans fatty acid consumption and colon cancer among Whites or African Americans. Those in the highest quartile of consumption had an adjusted odds ratio of 1.01 (95%CI 0.69, 1.49) for Whites and 0.99 (95%CI 0.61, 1.62) for African Americans when compared to participants in the lowest quartile. The North Carolina Colon Cancer Study II was similar to the above study except cases of distal colorectal cancer (present in the sigmoid colon, rectosigmoid, and rectum) were recruited from 2001-2006. An association was seen between trans fatty acid consumption and distal colorectal cancer in Whites, giving an adjusted odds ratio of 1.34 (95%CI 0.99, 1.83) for the comparison of the highest quartile of consumption to the lowest. For African Americans this adjusted odds ratio was 0.54 (95%CI 0.28, 1.02). In sum, the research presented in this dissertation demonstrated that high trans fatty acid consumption was positively associated with colorectal adenomas and cancers of the sigmoid colon, rectosigmoid, and rectum (in Whites). No association was present between consumption and cancers of the colon (cecum through sigmoid colon). Although further research needs to be done investigating the relationship for distal colorectal cancer in African Americans, as trans fatty acid consumption declines in the United States, rates of colorectal cancer may fall as well.